Clutch disk



Aw 39 @95E R. C. ZEIDLER 254x427 CLUTCH DISK Filed Aug. l5, 1946 y l 2 Sheets-Sheet l APM 3, W53 R. c. zElDLER 2,542,442?

CLUTCH DISK Filed Aug. 15, 1946 2 Sheets-Sheet 2 L2-@T fil@ T Vpatented Apr. 3, 1951 GLIi'nCH DISK Reinhold-e C. Zeidlerg. Detroit, Mich., nssignorttn` Btlrg.Vtnrner. Cnrporation,- Chicago, Ill., a cor-. l

poration ofrilllincis 'lj'hev present inventionV elateseto improvements infriction clutchesA o; the type which are adapted pigimarilmbut notegiclusivelvrfor use in auto- IiIQtiVe vehicles andr isfpart'icularlyv concerned with the structurewand form of; clutch discs oielle. webteam/pel which eerrr. the. frietiefnjelements of.' the cliltch plate drivenl membersv and` drinne memberseutefeetivegvehielee fiel?. exemple, e.d iee eizthiegtvpeis ,erdieerili etteehedto a driven shaft and' the disc is engaged'xvith pressure; between the eneine-A flywheel and an axially shiftablep ssure p1 temountedto rotate with the..dywheelg,teetvwheel'and meerdere pletedenstitnting driving leeuwen- An. ebieet .and eeeempliehment. O f: the invention is tdplouislea no l clutchv disc with friction elements Whichgwill take hold smoothly; and evenly when pressure is initially applied andjby; wielding. butrdpid.progressiveeenen Willamette the. clutch act quickly and eiciently Without grabbing. or jerking, AS.- d-further Obieet the invention eemereheddei the provision f d eluteh dise ef adequate Strength ferieorperaten i'nhieh powered' meter vehiieleel and which has requisite Ylexibility in its outer zene fer viel'dinelr. suppertine elutehrieteli elel- .mente er failings end is .dddDtdlel'et te be. etteehegd total hub structure, Whieh hubetreetilremer emr. bedr el vibration-damning..einen f,

Another ebieetef the intenti. is; termi/.ide f .el engagement between.the fretienelemeiitddld the driving and driven members throughout the applieation` oi. pressure tQeeeur-,e maximum edieierfiev. e rapid. progressive mevement and Without uneven wearon the friction elements;

A further objectofthenveiltQlis D0 movi??? afnvelydrivenlplate oi Simple, light., Sie@ SllbSfIlr tielV cpnstruction, which will give. longand eifreient service. and. Wh-eh will reduee spinning. movementgand thereby facilitate easy shifting of gears- H Another v'object of the invention s .to Y*provide a.T driven plate 0f Simple. eendirddiiO- li ddd. hdi/ing. reletivelvand vieldinelv. movable parte whereby to permit the clutch to take hold smoothlyJ evenly., and; q.11, ;k;ly;-andA Without setting` up vib 'ationszin the clutch andwithout ceurrving'v forward engine,

vibrations te. .the trerlemiesienf A featureof the ini/entione is, to. avoid theeifeet et localized. high preseurearfeesin theeluteh. fac: ieee ler previd ifer en eren. Dreereeeire dis: 1er-iederen,efV die eldia?. efleet in. the., evier zene di the driven. plete dise ever the entire. surieee efatee.rietieeieleneets 2; A further object. of?. the. invention. is.- to enable: initial contact ofthe outerfe'dges, off the two `iria?- tion elements With the grippingor.clampingipartm o f the driving member and a gradualfnrogressive. increase ofy contactradially ofy the. facingsloithe friction elements as the. pressure.. platel load is increased:-

Theinven-tion has,I for a further object, the provision ofa clutch disc having.its`.outer.zone or Vso-cal-l'ed-rifm sectinarranged tohavelyielding; elements which resist the compressingaction ofi the vfla-clings, and; these elements 'are incorporated directlyY in! the ymaterial which. forms the. body; ofi-the disc, i'

Another objectoithe invention. isto. provid'ea. clutch disc structure Whichhas its 'rimfsection the characteristic of` being yieldabl'ycompressible and which has portions lwhich yield, or.v flex. in such ccrnpressingac-tion, but which is..construct;.

` edr in one piecef'thus facilitating easy manutan- Y ture. endicosts. A

lnpresentda-yy automobilesethe trendistowardl larger and more powerful engines Accordingly, some4 of the clutch parts must ofi necessity. bei` made larger and heavier; retransmit povferjrom alarger engine, andaisofsor'ne oi' the other.pover transmitting parts may be. made heavierand; stronger including someof thel gears in the trans. mieder.

It- Will-'be appreciatedfbythesedshiiled inthe art thatav driven member of-theclutch. isCOnneCted directly toA certain of` the gears in the transmission and?tl'latV shifting of the gears. in. the transmission is effected by -irst releasing. the clutch so that the driven mem-ber, and the'. gears directly associated therewith, are free from fthe driving parts of the clutch. When the driven parts of the clutch, or the other driven I-)arts associated therewith?, are 'increased in Weight. and strength their momentum correspondingly. ine creases so that when the clutch. is released, the driven member ofthe clutch and the vga'rsin: the

transmission continue te rotate/with the result asse'rril'qlv andfrducing. manufacturing;

that itY isninieuift te shi-ft the gears.

olf example,y an automobile is started inY low gear, the clutch and-'theI gears associated tliierevvithl in the transmission 'arerotated at a rel-l entirely high, Seeed:- Wbenl die eldieh is Vr'eleldjeed teshifteeere-1iewerer. the eehtiiiued retedeii ef, .die driven. eert ei the. elutefiie'rild "geel". ree-eeen 0f medesima .fer dieilt e" and inlmany cases, clashing of the gear" te H.

eeeerdieeln it is edite. d rireedseslieiites 3 resultant momentum of the driven parts, thus minimizing the tendency of continued rotation of the driven parts after release of the clutch. This facilitates gear shifting.

The present necessity of making clutch discs larger and stronger to accommodate the trend toward higher horse power engines, has presented an acute problem of flexibility of the clutch discs particularly in its oute` zones; the flexibility of the disc in its outer zone provides a cushioning effect of the clutch plate to damped vibrations and to prevent chattering of the clutch.

In the designing of a clutch disc, in order to obtain smooth engagement when starting up from stand-still, it is desirable to have the rim section of the disc to which the friction facings are attached formed in such a manner so that application of the load of the clutch pressure springs causes gradual flattening out of this form. This form must be of a nature so that the facings are properly supported with a maximum amount of supporting area during the initial flattening out of the disc.

Clutch plates have heretofore been made in various forms and they usually comprise a metal disc made fast to a hub and friction facings secured to the disc on opposite sides thereof adjacent the periphery of the disc and adapted to be located between the clamping parts of the driving member.

In one type of disc the desired flexibility in the rim section isobtained by grinding this portion only to a close tolerance reducing its thickness substantially. An example of this is a disc made of .050 inch thick sheet steel with the rim section reduced to .033 inch by this method.

. In another disc the flexibility in the rim section is obtained by letting this section be comprised of a number of individually formed spring steel segments of about .020 inch thickness having legs extending inwardly of the friction facings and riveted to an intermediate plate of substantial thickness giving it the necessary strength to withstand failure.

Other types of discs consist of plates as large in diameter-as the outside of the friction facings havingattached to one side in the rim section a series of spring steel segments or cushions of various designs and forms with usually one facing attached directly to the plate `and the other attached to the cushions. It is an object of this invention to eliminate expensive grinding operations as well as the need for elaborate equipment; a further object is the elimination of additional parts in the form of individual segments, rivets and subsequent assembly labor involved.

Accordingly, the present invention contemplates a clutch disc formed by cold rolling the material to a suitable thickness, such as .040 to '.043 or if necessary, to even closer tolerance or other thickness. This rolling operation would be performed by the supplier of the sheet steel of whom there are many skilled in the art of producing high carbon sheet steel to close thickness tolerances at economical cost. The thickness of the material is the same all over, thereby permitting a disc of adequate thickness and strength to be selected and the flexibility in the rim section being achieved by an improved relative disposition and shape of the perforations in the rim section and by theform produced in the rim section.

i Other objects, features and advantages of the invention will be apparentfrom the following 4 description and the accompanying drawings, in which similar characters of reference indicate similar parts throughout the several views.

Referring to the two sheets of drawings accompanying the specification:

Fig. 1 is a fragmentary elevational view of a clutch driven plate embodying the invention;

Fig. 2 is an axial sectional view taken substantially as indicated by the line 2-2 of Fig. 1;

Fig. 3 is a fragmentary View looking at the periphery of the clutch driven plate depicted in Fig. 1;

Fig. 4 is an enlarged elevational View of one sector of the outer zone of the disc;

Fig. 5 is a fragmentary sectional view taken substantially on the line 5 5 of Fig. 4; and

Fig. 6 illustrates a deflection curve obtained with the disc constructed in accordance with this invention.

I In an exemplary embodiment of this invention, depicted in Figs. l and 2, a clutch driven member, which is designated in its entirety by the numeral 20, comprises in general a metal disc 2| having xedly secured thereto friction elements or facings 22 which are adapted to be packed between conventional driving members (not shown) of a friction clutch. The inner zone of the disc 2| is mounted upon a hub 23 which may have an integrally formed flange 24 and splined as at 25 for attachment to a driven shaft (not shown).

A vibration dampening structure is associated with the disc 2| and the flange 24 to provide a flexible driving arrangement between them. For this purpose the disc 2| and the hub 24 may be connected by an arrangement in the form of an annulus of coiled springs 26 located in aligned openings in the disc 2|, flange 24 and washer 2l. The openings in the disc are shown at 28. The openings in the flange are shown at 29, and the openings in the washer are shown at 30. The disc 2| and washer 21 are connected together for movement in unison, and to this end they may be joined by long rivets 3| (Fig. 2) having an enlarged center portion 32 for maintaining the disc and washer in parallel planes in spaced relationship to each other. The rivets 3| also carry an oil shield 21a. The rivets 3| may pass through notches 33 in the hub ange 24 with considerable clearance to permit relative movement between the disc and the Washer on the one hand and the hub on the other, as the springs are flexed.

This movement may be controlled and dampened by friction material 34 disposed between the disc and the hub flange and between the washer and the hub fiange.- Driving forces are transmitted from the disc 2| to the hub 23 and vice versa through the coil springs 26, and when they flex there is a spring loaded friction action afforded between the friction material 34.

It will be observed that the openings 28, 3U in the disc and washer respectively, have a radial dimension less than the diameter of the spring, and accordingly the springs are held in the aligned apertures.

The coil springs, of course, are of high carbon steel, and in order to provide a substantial factor for the holding of the springs in the aperture, the disc 2| and the washer 2l are preferably of high carbon heat-treated steel so as to minimize Wear tending to enlarge the apertures therein, such an enlargement may allow the springs to fall out. Moreover, the apertures in the disc and washer are so formed, preferably,

amin-iii as improvise-"asurface contactar/tumeshing;

a'nd for this'purposethewalls ofthe apertures" bingaction on the spring,A but merely abut'ag'ainst'V the" spring` ends.. 'It will also'b'e observed that their'adially outwardwa'll ofthe apertures'in each member` is of curved formation, advantageously I ourv'ed'on an are 'around'the `hun center, so that sufficient' clearance i's afforded'in' order that"v there viiill'not be a binding.' action' on the.y spring/con#` volutions when thesame are flexed'. The springs 2`are of straight'andcylindrical form in over'- all' dimensions and' whenv one end is'pickedup' by. a driving or vibration force"and"shifted rela' tiveftthe' walls ofthe' apertures'the' sameA moves infar a'rc' around the" center, and theoutside walls' oftheapertures' may 'be lfrnied on a paralleling' arcjtomaintain clearance'.

Preferably, the springs" are under some compression when the apertures are in alignment,` and as a result the springs ZG'aretensioned/'more their portions radially'renioved from'the axis of" rotation than in' the portions next adjacent the axis" of rotation; this' accordingly tends' to' lir'ge'the springs' bodily'inwardly, thereby over# coming. a centrifugal'forc'e,.tending to throw the Springs radially outwardly.r Accordingly, the springslZE 'are' p'ositionedin a more or less neutralmanner in the apertures and scrubbing" `or rubbingV between the" springs andthe outer Walls' iiithe apertures' due to centrifugal force' is ,miniinize'd'; l

In" the arrangement shown herein, six coil springs'26` are use'd'in thev annu'lus, and in structures of higher torque capacity, eight or ten, or more; springs may be required. Preferably, the corners ofthe apertures are somewhat rounded, asat'` 39; and this may bein` the hub an'ge 24', disc 2l', and washer 21,. to minimize any tendency of' the' metal to crack or split at these points. Moreover,.it is preferable that the end convolu# tions of' the 'springs 2`6'be'rou'nde'd off at the edges `which would tendV to "c'ause'exces'sive wear on the Wall'softhe apertures.' u Y y The assembly hereinb'efore'" described is` very easilym'ade; as the' parts may be" properly posi# tifoned, the springs inserted in the apertures, and the' several'rivets' conn'c'e'ct'ngV the parts spun over tri-complete the" assembly. This eliminates any threading operationv which isnece's'sary where tlfieL springs are held in placeby` strips, wires' or" ei nts' threaded through the springsi ving" thus r described one form of*y vibration da 'peni-ng arrangement which may be advantageously employed in the present invention, the disc Z and' its construction and form will now be described in detail.

Referring to Figs. 1 and 4, the disc body ad# 'varita'geously is 'of 'spoke' construction, particul'arly' in itsouter zone: Y As illustrated in-"Fig'- 4, the' spokes are in' the" form of cushion members generally'indicated in' their" entirety' by thenumeral- E?! and each' having a neck` 42 and an; enlargedhead- 3; The-head 43; as illustrated, may .lie visualized as havingthree portions, namely, a 'center portion il? and end portions i5 and 46 ori-'opposite sides thereof all disposed obliquely tothe inner Zone of? the' disc 21|). The end por"A 455 is provided with lands Hf and 48 andthe endiporticnsa is'. provided' with lands 491 and 50'; lbisposedbetiveen; adjacent lands-are openings or apertures 5|, 52 and 53, and an opening lillv` removed. to opposite sides thereof.

disposed in' the*neck1V portion' 112` importanti feature oft the' invention' isLA the specific shape;- posi'ti'on', and structure'ofthe'flandssand the rela--v tive disposition oftheo'penings` betweenthese-'- lands:

Thev cooperating function of these elements Willbe hereinafter' explained in detail.V

Accordinge to thisconstruction and arrange-'- ment, ea'ch"V s'poke'o'rv cushion member has' aA twisted or'oblique formation 44 substantially' centralized cna radial line therein through the-cen@- ter' of" the' neck portions?. Between the center` portion 4"@ andthe end'landsll'l and 5U are b'en'd1 lines' 55"-68',. arranged so that'the lands 41 and lleand the'lands 48' and 5i); increase' in height ini'a radially'outward'direction and are disposed inplan'es slightlyoff'parallel tothe plane-'of the disc. Meaning that while theland surfaces' themselves' are 'substantially 'at'they lie in con'- ical relation with" each otherv with every'other one* tapered' in one" direction' and' those in' be`` tween being-'tapered in the opposite 'dire'ction'thus' giving' in effect a series' of concave surfaces'on' each'sideof'the disc. Thev lands 41" and 49 lie in one common plane andthe lands 48 and 50 lie.' in another' common plane, with the common planes diverging outwardly in a region beyond' the Zone of' the disc 2|. Surfaces 41 'a'nd'lltl'l wouldhave the same relation to the body of the disc surfaces 48j and 5D" b'ut wouldbeaxially While 'su`r' faces 4l', de, @and 5U'are flat'within themselves andtapr in a conical.' radial manner, connectirigl lsurfaces' de, 635 and`4`5. are not fla-t in themselvesbut have a variable taper in a circumferential direction. For example surface IMq across C has a much greater taper than at D because C. is shorter and the height between T andS is greater. In the actual formation, the bend lines do not'appear. abrupt, but appear a good deal lilie theV illustration shown inl Fig. 3. The shading in Fig. 4 is slightly exaggerated to demonstrate the formation.

Two friction facings El and 62 are xedly secured'to the disc, one on. one side and one on the other. v The friction facing 62 is secured to the land 48 as, for example, by suitable rivets 63.'.3 `The friction facing 6l is secured to the land de by similar rivets 6. It is notable that each spoke is formed like the one just described, so thatV respective lands of. each spoke project to the*v same side of the center plane of the, disc and are in a position to be secured to the facings in like manner as hereinbefore described.

The facing Viii may be provided with clearance apertures 65. for the ,heads of the rivets 63, and the facing 62 may be provided with clearance apertures 5.6 for the rivets 64.

According to this construction andv arrangement of parts-the facings 6| and 62 are normally held in axially spaced relation, but. they arey ca'.- pable: of moving` toward eachother a's the disc is' collapsed or compressed. incident to being packed by theV clutch. driving members.

Referring to" Fig. l, the shape and position of theperforations or' apertures 5l, 52 and 53 sucht-,hat the width A atr the outer edge is greater thanrB at the.. inner edge, and this is relative to the difference' in the width. of the spoke X, measured eircumferentially along the outer peripheraledgef, as compared to Y, measured alongthe inner' peripheral edge. In' other words, X is longer'th'an Y and if the width A were the same at' the-'outside as itis at the' inside as at B, it would result in the outer' portion of theY discbeing considerably softer than the inner portion, with the result that the relative resistance to flattening out would be greater at the inside and would show a heavier wear pattern at the Vinner diameter of the friction facings. By making the dimension A greater at the outside than B, the resistance to flattening out is just slightly greater at the outside than at the inside.

It is important that these perforations 5|, 52 and 53 do not cut through that portion of the disc which supports the facings, in other words, the lands 41, 48, 49 and 5). These lands are the principal supporting surfaces for the friction facings. As engagement of the clutch progresses the unit pressure between the lands and the backs of the facings increases proportionately reaching a maximum when the rimlsection becomes substantially fiat under full spring load. It is only at this time that surfaces 44, 45 and 46 have any appreciable contact with the facings and this is only under relatively light unit pressure. It should be noted that the shape of the perforations produce arms of a variable width, so that the distribution of stresses due to bending when flattening are more uniform. This is illustrated by the width of the arm at V being greater than at A and at Z being greater than at B. The additional perforation 54 in the neck 42 of the spoke 4l is to reduce the stiffness at this point to lessen torsional resistance.

Referring to Fig. 4, apertures 68 and 69 are provided as a convenient means to permit attaching of balance correction weights (not shown). Two of these apertures are provided in the disc body at each of the T-shaped spokes as shown.

In many of the prior art structures, the neck of the spoke is so constructed to deliberately build up a torsional resistance to aid in the resistanoe to the deflection of the rim section. In the present invention, no torsional resistance from the neck is desired, and an effort is made to reduce this to a minimum-henca the additional perforation 54.

According to this construction and arrangement of parts, it is notable that when the disc is placed on a fiat surface, points S and U contact the surface, while the points O and M are slightly raised, or higher. Likewise, if an indicator were put on the points T and R, then again at N and P, it would be found that the two latter points are slightly lower. In other words, the form height, or the distance from the lowest to the highest measured point around the outer peripheral edge of the disc, is considerably greater than the same measurements taken around the inner portion of the disc. It is notable that these measurements will be approximately the same whichever side of the disc is upward indicating that both sides are in effect concave and symmetrical. This is illustrated in Fig. 5 wherein the distance between the points K-K is greater than the distance between pthe points L-L. In placing a straight edge across either of the facings, it will be noted that the facings, which are normally fiat, have been caused to become slightly concave due to the form in the disc. This formation gives what might be termed a rolling in action, and helps to give the desired softness under light loads. By varying the amount of taper in the lands 4l to 53, the degree of flexibility is likewise varied. Moreover, this form assists in obtaining a heavier wear pattern on the friction facings toward the outer diameter. Actual experience indicates that smoother engagement and better performance is obtained if the wear pattern is heavier toward the outside rather than toward the inside. Measured circumferentially, more facing area exists at the outside; and with the higher unit pressures nearer the outside, greater torque capacity is obtained from a given diameter of clutch. It is not important to have full contact at initial engagement; in fact progressive contact is preferred since it will aid in obtaining quick release. Therefore, the tapered construction set forth above will allow the clamping members of the clutch to initially contact with the facings at the outer edges thereof and this contact will progressively increase radially of the facings with the increase of pressure of the clamping members.

In the past it has been found in some installations where the facings make full initial contact, there is a tendency for the facings to adhere to the driving surfaces causing spin or drag when the clutch is released. This adherence is similar to what occurs when Johansson gage blocks are rubbed together.

he lands, although higher at the outside than the inside, are otherwise relatively at in themselves and constitute the supporting area for the two friction facings 6l and 62, which are independently riveted to the disc. During the initial engagement of the clutch, when slippage is actually taking place, the form in the rim section is only partly flattened out, so that these same areas, whether or not perforated, would still be the principal support for the friction facings. As engagement progresses and the disc becomes substantially nat, these supporting areas or lands increase slightly in width so that in effect, the perforations begin to overlap into the supporting area. However, it is important to understand that at this stage of engagement relative slippage between the friction facings and the flywheel and pressure plate surfaces has almost ceased, so that the question of facing support at this stage is not too important.

It will be noted that the form height from point S to point T may be approximately .058 while from O to N would be .039. The lands are tapered from outside to the inside while the areas between are tapered both from the outside to the inside as well as transversely. Therefore, the dimension C, as measured at the outside, has a much higher degree of taper than the dimension D measured at the inside. This lesser degree of taper at the inside, plus the addition of the perforation 54, reduces the torsional resistance of the neck of the spoke to such an extent thatl it has very little influence on the overall stiffness at the inner portion of the spoke. 'I'he stiffness then at this point is controlled almost entirely by the width and length of the arms B and Z.

In the present arrangement, a greater number of cushion members of the type hereinbefore described may be disposed in annular array on a given radius, and this provides an increased number of points or locations of support for the facings. These points or locations yieldably resist compression action during clutch engagement, and as a result there is an increased area on the facings which resist compression, and a correspondingly decreased unit pressure. 'Ihe structure of the present invention contributes to a smoothly acting clutch and decreases a tendency for the clutch to chatter or grab during clutch engagement.

Moreoven .thecdistance between points of support,maybeofadequate length Without decreassing .the number `of supporting points. It-.Will be lunderstood, of Icourse, that 4where .thedistance between .supporting points .is .short resistance to .-riexure .is increased. As ;a result, thefstockof which the disc l member-is made, need 4not be so rthick, and, accordingly, the desired type and `y,gauge of stock .mayv be employed. l

: lNew as the clutch disc of the present invention lisengaged, the facings approach each other and Lyvithlands M and 49 contacting one facing and 148and 50 contacting Ythe other facing there .is fa-,bending action tending to flatten out the spoke head. Preferably each spokehead is formed so @that its 'width measured circumferentially Vin :Lits-.outer acne is greater than its width in its in- ;fnerizone. ,Also vthe side edges 6l are straight as Vs hownto insure more uniform contact with vthe :facings lto effect the .best l Wear pattern.

.Another important advantage of the structure ,of --thespoke Vof the-present invention is that it -reduces themoment of inertia of the clutch disc in operation. When Ya ;quick gear shift is Y made, n-so that there is practically no change in car speed during the shifting period, the speed ofthe driven member, after, the clutch has been released, must .Lhe `changed quickly to `correspond to the 'new gearratio With modern passenger'car transfmissions, this change is assisted bysynchronizing `devices If the gears areengaged while not r'in `f fsynchronisni, an impact isproducedon the engaging f'surfaces, gear teeth :or clutch jaws, and :themagnitude of this impact Aalso depends upon the: moment of inertia ofthe clutch drivenmem- Auber. A low :moment l of inertia of the clutch mem-ber, therefore, makes for-easy shifting yand :Quiet-operation. -.Si-nce the `moment of inertia isequal to the sum .of the products of all mass particles into the squares-of their distances from the axis, it is particularly important to keep downthe weight in the rim. This is accomplished in the present invention by judicious placement of the perforations which not only cut down the `Weight in the rim section, but also assist in the .deflection pattern of the rim section.

, ,In the clutchL disc ,of this type it is desirable, .that initiallcompression .takes lplace against a relatively low resistance, but wherein the resistance increases as the compression ofthe disc continues. A curve plotted to show this desired characteristic is oneAWh-ich is vrelatively :soft :or `iiat in `thc early stages ,of clutch engagement and .such a curve is illustrated in Fig. 6. In referring to .the plotted curve depicted in'Fig. '6, it is :notable thatthe curve is fairly soft initially, and, in fact,.a load of aboutO pounds causes adeflec- .tOn-Of approximately .035. of an inch. Atabout 1,500 pounds -of loadthe ydeflection has increased to lapproximately .055 of van inch, it being apparent that the-iinal 1,000 poundsof Vload irl- .creases the deflection only about .020 of an inch.

In the present design, the deilection pattern :is .controlled (l) lby thefrelative disposition and ;shapeof the perforations in the rim section,z (2) .sby theform produced in the rim section and (3) by the thickness of the material. Oncesnumber 11,1) is `determined for ;a given ,diameter of disc itbeconiesaan. easymatter to 4vary the deflection characteristics by chang-ing v theform or easier ychanging -thethi-ckness Ultimately their. .nent L-formation will .be packed acings and-.then nnen .the ,-anpleaased v:clutch pnessur-e the tendency In the 'form of `clutch disc 2| of the present invention, a good Wear ,pattern on the facing 'is provided because 'ofthe manypoints of Support atb vwgiven Yto vthe -facings and because the 'supports :extend-substantially completelyiacross the facinggs from the :in-ner :to the outer peripheral edges. Xlthcmghpthe nlutch discfZl 'illustrated hereinhas "been .described as having eightspokes, any num- --20 'ber of'spokes maybe employedas desired. Where weightl spokes `are employed, sixteen'initial supportng lands foreach facing are provided with v"the supports alternating on the facings vand extending `'substantially completely across the ggyffacings. VThe spoke heads 4I act as units in their entirety as differentiated from struck out tongues or portions vas :found in prior art construction; ;this lcontributes vto the obtaining `of -a satisfactory wearpattern. ln this matter of 5,30 "constructionthere, are .no localized points or hspots `which essentiallyl support the facings and which would vbe designed Ato igiueabad Wear pattern. The discs 2| ,of the present invention may be yaried or.. modiiied vvto obtain different deection 135 curves in vorderthat the; mostsatisfactory clutch disc mayi be selected Yfor a lparticular vehicle or model of .that vehiclegbymerely selecting the 'properthicknessof Adisc stock. |Ihe shapefarid form of each disc being the same would` necessi- .40 tate only `one ,stamping `lixturejfor Vall the .differ- .ent designs.

and time.

AIt will, therefore, be seen that the present invention provides a clutch `disc which obtains 45, a desired deectioncurve and atlthesame time this is'accomplished without the use ofA separate vspring inserts and other expensive features found l'in prior .art structures. In fact, aminimum num- !ber of parts are required, `name1y,.the discpZl 50 vitself and two facings. Of course, the invention Y,caribe used without the vibration dampening hub construction ihereinbefore described, in which event thedisc 12.! may be fastened directly to the hub. VThus the invention not Vonly Iprovides a ,.55 structure wherein Ya desired nicety of V.oleiiection A ,isobtaine'dg Lbutatthe Same time provides a clutch Ymember uniformly simple .in construction and .composed .of `ra minimum number ofparts..

'The .advantagesof `the present, clutch .discmayl 50 therefore. be 'summarized as follow/s:

.,1.-,;C apable of picking up its load smoothly, evenly, andV Without grablor chatter;

'2. Low vmoment of inertia Vto permit ,easygear shifting;

Q3. Dampensout .any vibration of the vcrank-- shaft to ,prevent gearclatter;

4. E,es'ly.varie d to suit. a particular make tof arehicle.:

VY5.. Economical `to manufacture; onepiece con- ,7o struction;

6. Eacingslcan..bereadil-yserviced thefeld. While 1.1. have .illustrated 1.a preferred embodi- :unent o f;-my in ention, ma modieatonsimay d oin--rthessrritiofthe tot'lbel-imiteditogthe This is a great saving in expense intenzionata precise details of construction set forth, but desire vto avail mysef of all changes within the scope of the appended claims.

I claim:

1. A clutch driven member comprising axially spaced friction facines; a disc having an inner zone adapted for connection to a hub, and having an outer zone adapted to support said facings, said outer Zone being defined by a plurality of cushion members each comprising a circumferentially extending bodynortion lying between said facings, and a neck connecting said body portion to the outer periphery of said inner Zone of the disc, each cushion member having a central section lying in a plane oblique to the plane of said inner zone and having an aperture therein with circumferentiallv spaced side edges said aperture occupying a substantif-l portion of the area of said central section, first and second radial lands at the opposite circumferentiallv spaced side edges of said aperture and havingr radial cides terminatinrv at said apartme side edges so that the sides with oortionsthereof of said lands are not interrupted by said aoerture, said lands lying in panes which are axially spaced from said plane of said inner zone; third and fourth radial lands at the end regions of each cushion member having radial sides and being spaced circumferentially from said first and second lands, said third and fourth lands lying in planes which are axiallv spaced from said plane of said inner zone, said first and third lands lvine in a common pane and contacting one of said facings, and said second and fourth lands also lying in a .common plane spaced from said last-mentioned.

plane and contacting the other of said facings,

- and two circumferentially spaced sections in each cushion member between which said central section and the respective first and second lands are disposed, eafh of said two sections being disposed between and connecting two adjacent ra dial lands and being spaced from the friction facings and arranged in a plane oblique to the plane of said inner zone, each of said two sections having an aperture therein occupving a substantial prtion of the area thereof and the aperture having circumferentially spaced side edges terminating at the sides of the two adjacent radial lands so that the sides of the lands are not interrupted by the aperture; and means securing one of the lands contacting one friction facing to said one friction facing and means securing one of the lands contacting the other friction facing to said other friction facing.

2. A clutch driven member comprising axially spaced friction facings; a, disc having an inner zone adapted for connection to a hub, and havmg an outer zone adapted to support said facings, said outer zone being defined by a plurality of cushion members each comprising e, circumferentially extending body lying between said facings, and a neck connecting said cushion body to said inner zone of the disc, each cushion member having a central portion arranged in a plane oblique to the plane of said inner zone and spaced from said friction facings and having an aperture therein radially aligned with said neck,l said aperture having circumferentially spaced side edges and occupying a substantial portion ofthe area of said central section, radially extending portions lying in planes oblique to the plane of said inner zone and being spaced circumferentially from said central portion and also spaced axially from said frictionfacings and having side edges with said apertures occupying a substantial portion of the area of said radially extending portions, radial lands intermediate and connecting said central portion and respective of said radially extending portions and having radial sides with portions thereof terminating at one of the circumferentially spaced side edges of said apertures in said central portion and radially extending portions, respectively, so that the sides of the lands are not interrupted by said apertures, and radial end lands circumferentially spaced from but connected to said radially extending portions and having radial sides with portions thereof terminating at the other of the circumferentially spaced side edges of said last-mentioned apertures so that the sides of said end lands are not interrupted thereby, one of said radial intermediate lands and one of said end lands lying in. a common plane and engaging one of said friction facings and the other of said radial intermediate and end lands lying in a common plane and engaging the other of said facings; and means securing one of the lands engaging one friction facing to said one friction facing and means securing one of the lands engaging the other friction facing to said other friction facing.

3. A clutch driven member as defined in claim 2, in which the inner Zone of the disc is disposed in a plane transverse to the axis of rotation thereof and in which the common plane of the one end land and the one intermediate land is on one side of and inclinedin one direction relative to the plane of said inner zone, and in which the common plane of the other end land and the other intermediate land is on the other side of and inclined in an opposite direction relative to the plane of said inner zone, the directions of the said common planes of said lands diverging outwardly in a region radially beyond said inner zone, whereby the outer faces of the friction facings engaged thereby normally assume a slightly concave shape when not under clutch engaging pressure.

Ll. A clutch driven member comprising axially spaced friction facings; a disc having an inner zone adapted for connection to a hub, and having an outer zone adapted to support said facings, said outer zone being defined by a plurality of cushion members each comprising a circumferentially extending body lying between said facings, and a neck connecting said cushion body to said inner zone of the disc, each cushion member having a central portion arranged in a plane oblique to the plane of said inner zone and spaced from said friction facings and having an aperture therein radially aligned with said neck, radially extending portions lying in planes oblique to the plane of said inner zone and being spaced circumferentially from the sides of said central portion and also spaced axially from said friction facings and having apertures therein, all of said apertures having circumferentially spaced side edges, radial lands intermediate and connecting said central portion and respective of said radially extending portions and with portions of said lands terminating at the circumferentially spaced side edges of said apertures and not being interrupted thereby, and radial end lands circumferentially spaced from but connected to said radially extending portions and with portions of said last-mentioned lands terminating at the adjacent side edges of the apertures therein and not being apertures therein with circumferentially spaced mediate lands and one of said end lands lying in a coin-mon plane and engaging one of said friction facings and the other of said radial intermediate and end lands lying in a common'plane and engaging the other of said facings, the aper ture in each of said radially extending portions having radially extending side edges of diiferent lengths to provide circumferentialiy tapered radially spaced inner and outer arm portions converging toward the aperture of said central portion and connecting a radial intermediate land to an end land; and means securing one of the lands engaging one friction facing to said one friction facing and means securing one of the lands engaging the other friction facing to said other friction facing.

5. A clutch driven member defined in claim 4, wherein the central oblique portion converges radially outwardly of said disc and the radially extending oblique portions and intermediate lands converge radially inwardly toward the inner zone of the disc.

6. A clutch driven member comprising axially spaced friction facings; a disc having an inner zone adapted for connectionfto a hub, and having an outer zone adapted to support said facings,

said outer Zone being defined by a plurality of cushion members each comprising a circumferentially extending body lying between said facings, and a neck connecting said body to the outer periphery of said inner Zone of the disc, the body of each cushion member having a radially extending central portion arranged in a plane oblique to the planes of said disc and said facings and spaced from said facings, said central portion having an aperture therein providing radially spaced inner and outer parts in said central portion, radially extending oblique side portions spaced circumferentially from said central radial portion and axially spaced from said friction facings and each having a radially elongated aperture therein providing radially spaced inner and outer parts in said oblique side portions, radial intermediate lands between said central portion and said oblique side portions and connecting said radially spaced inner and outer parts of said central and oblique side portions, and radial end lands connected to said radially spaced inner and outer parts of said oblique side portions, each of said apertures having side edges extending radially and terminating at and being defined by the edges of the lands adjacent thereto, one of said intermediate lands andone of said end lands lying in a common plane parallel to one of said facings and engaging said one facing and the other of said intermediate and end lands lying in a common plane parallel to the other of said facings and engaging said other facing; and means securing one of the lands engaging one friction facing to said one friction facing and means securing one of the lands engaging the other friction facing to said other friction facing.

7. A cushion device for use in a friction clutch, comprising: a resiliently metal member having an elongated body and a neck extending from one longitudinal edge thereof and a flat attaching portion integral with said neck for connecting the same with a support, said elongated body portion having a transversely extending land at each end thereof and two intermediate transversely extending lands spaced from each other by a central section and respectively spaced from said end lands by an intermediate section, all of said lands having substantially straight uninterrupted side edges and bend lines, said central section lying in a plane oblique to the plane of said flat attaching portion and having a circumferentially elongated aperture extending thereacross with two of the opposite sides of said aperture defined by the adjacent straight side edges of said intermediate lands, said intermediate sections respectively lying in planes oblique to the plane of said at attaching portion, each of said intermediate sections having a radially elongated aperture extending thereacross with opposite sides of said apertures defined by the adjacent straight side edges of an end land and an intermediate land, one end land and the intermediate land most remote therefrom being disposed in a substantially common plane and adapted to engage a first friction facing and the remaining end land and intermediate land being disposed in a substantially common plane axially spaced from said first-mentioned common plane and adapted to engage a second friction facing.

8. A cushion device as defined in claim 7, in which the lands gradually increase in height in a. direction away from the longitudinal edge of the body portion having the neck extending therefrom.

9. A cushion member as defined in claim 7, in which all of the lands gradually increase in height in a direction away from the longitudinal edge of the body portion having the neck extending therefrom and in which the intermediate lands gradually increase in circumferential width in the stated direction.

REINHOLD C. ZEIDLER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,659,289 Gamble Feb. 14, 1928 2,277,603 Nutt et a1 Mar. 24, 1942 2,283,113 Wemp May l2, 1942 2,307,006 Wemp Dec. 29, 1942 FOREIGN PATENTS Number Country Date 499,881 Great Britain Jan. 31, 1939 

